1. Field of the Invention
The present invention relates to the field of organic light-emitting diode, and in particular to an active matrix organic light-emitting diode and a manufacturing method thereof.
2. The Related Arts
An organic light-emitting diode or organic light-emitting diode display (OLED) is also referred to as an organic electroluminescent diode, which is a novel displaying technology of which the development was dated back to the middle of the 20th century. The organic electroluminescent diode has various advantages over a liquid crystal display, such as being fully solid state, active emission of light, high brightness, high contrast, being ultra thin, low cost, low power consumption, fast response, wide view angle, wide range of operation temperature, and being capable of flexible displaying. The structure of an organic electroluminescent diode generally comprises a substrate, an anode, a cathode, and an organic function layer and the principle of light emission is that multiple layers of organic materials that are of extremely small thickness is formed between the anode and the cathode through vapor deposition, whereby positive and negative carriers, when injected into the organic semiconductor films, re-combine with each other to generate light. The organic function layer of the organic electroluminescent diode is generally made up of three function layers, which are respectively a hole transport layer (HTL), an emissive layer (EML), and an electron transport layer (ETL). Each of the function layers can be a single layer or more than one layer. For example, the hole transport layer sometimes is further divided into a hole injection layer and a hole transport layer and the electron transport layer may also be divided into an electron transport layer and an electron injection layer. However, they are of substantially the same function and are thus collectively referred to as the hole transport layer and the electron transport layer.
Currently, the manufacture of a full color organic electroluminescent diode is generally done with three methods, which are RGB juxtaposition and individual emission method, white light in combination with color filter method, and color conversion method, among which the RGB juxtaposition and individual emission method is most promising and has the most practical applications. The manufacturing method thereof is that red, green, and blue use different subject and object light-emitting materials.
The organic light-emitting diodes can be classified in two types, according to the method of driving, which are active driving and passive driving, namely direct addressing and TFT (Thin-Film Transistor) matrix addressing. The active driving type organic light-emitting diode is the so called active matrix organic light-emitting diode (AMOLED). Referring to FIGS. 1 and 2, an active matrix organic light-emitting diode comprises a substrate 100, a TFT array 300 arranged on the substrate 100, and an organic light-emitting diode body 500 arranged above the TFT array 300 and electrically connected to the TFT array 300, and an insulation layer 700 arranged between the TFT array 300 and the organic light-emitting diodes body 500 and is usually composed of a structure of 8-12 layers. The greater the number of the layers is, the more complicated the manufacturing process will be and the greater the number of masks used. And, the manufacturing efficiency and product quality are getting worse and the manufacturing cost is getting higher. Further, an excessively large area occupied by a storage capacitor also reduces the aperture ratio of a pixel unit. Thus, the manufacturing method of an active matrix organic light-emitting diode must be further improved.